The human body has curves of varying curvature and various folds. To perform optimally, absorbent articles worn close to the body need to conform to the shapes of the body's curves and folds. Absorbent articles are typically comprised of multiple layers of materials that are thin relative to their planar dimensions. Thus, one problem facing designers of absorbent articles to be worn close to the body is how to translate what are essentially two-dimensional pieces of material into a shape that conforms to a three-dimensional shape.
Absorbent articles worn close to the body perform by capturing excretions of fluids from the body. For absorbent articles including sanitary napkins, panti-liners, incontinence articles, diapers, and breast pads, the portion of the body from which the excretions emanate are well defined. Designers desire that these types of absorbent articles remain in close contact with the wearer's body so that the absorbent article captures the fluid without permitting any fluid to bypass the absorbent article. Fluid that bypasses an absorbent article worn close to the body can end up soiling the wearer's outer clothing, resulting in a potentially embarrassing situation.
Wearers of absorbent articles are involved in a wide variety of activities in which the shape of the body is continually changing. For instance, an infant diaper wearer may spend part of her day lying down and sitting and another part of her day crawling. Similarly, adults are involved in a wide range of activities ranging from lying and sitting to running and playing sports. The absorbent article that an adult wears needs to fit her body throughout a range of different activities.
One approach to designing the shape of absorbent articles is to create body forms, such as mannequins, having a variety of body geometries and body positions and placing prototypes of absorbent articles in contact with the body form to evaluate how well they fit the body form. If the absorbent article does not fit the body form well, the designer alters the shape of the absorbent article. The designer may alter the shape of the article by adding or removing material and may alter the thickness or thinness of the absorbent article. This approach to design can be cumbersome and may not yield the optimum conformance of the absorbent article. One possible reason that this approach may not lead to satisfactory results is because the design problem is viewed as “how can a three dimensional shape be designed to conform to a body?” An alternative view is to frame the design problem as “what shapes of two dimensional materials can be used to form a three-dimensional absorbent article that conforms to a body?” Another approach to designing the shape of absorbent articles is to use three-dimensional images of bodies collected using a device such as a magnetic resonance imaging apparatus. Magnetic resonance imaging can provide exceptionally detailed information on the shape of the surface of the human body. To use this method, a designer must have access to an expensive imaging device, computational tools enabling analysis and manipulation of collected images, and subjects who are able and willing to submit to being imaged.
There is a continuing unaddressed need for methods for designing absorbent articles that conform to the shape of the body. There is a continuing unaddressed need for methods for designing absorbent articles that conform to the shape of the body that are inexpensive to use and relatively easy to perform.